Sub-lethal effects of organophosphates and synthetic pyrethroid insecticides on muscle tissue transaminases of Oreochromis niloticus in vivo.

Abstract

Organophosphates and synthetic pyrethroid insecticides have been commonly used in public health and agriculture. The present study aimed to evaluate the sub-lethal effects of organophosphates and synthetic pyrethroid insecticides on transaminases: glutamate oxaloacetate/aspartate transaminase (AST) and glutamate pyruvate/alanine transaminase (ALT) in Oreochromis niloticus. Fish were exposed to malathion (OP), chlorpyrifos (OP) and λ-cyhalothrin (synthetic pyrethroid) at sub-lethal concentrations of 1.425, 0.125 and 0.0039ppm, respectively for 24 and 48h. AST and ALT activities were shown to be remarkably (p < 0.05) decreased and increased, respectively in O. niloticus treated with the insecticides. The highest and lowest inhibition in AST level were noted as -12.2% and -12.2% in chlorpyrifos and λ-cyhalothrin 24h treated fish samples, respectively. The highest and lowest elevation in ALT level were recorded as + 313% and 237% in 48h chlorpyrifos and 24h malathion treated fish samples, respectively. This indicates that the insecticides used in this study did not result in death but in changes in AST and ALT enzyme activities. Therefore, organophosphates (malathion, chlorpyrifos) and synthetic pyrethroid (λ-cyhalothrin) insecticides are toxic to fishes and could affects their survival in their natural habitat.